“Moreover, there was evidence of a dose-response relationship between the number of care processes a patient received and mortality,” the researchers write. Based on the study’s findings, they estimate that 57.3 percent of the decrease in risk-adjusted mortality could be attributed to increased use of care processes.

“Perhaps the most surprising finding was that it was clear that the more evidence-based care processes a patient receives, the lower the likelihood of death,” Dr. Goto said. Although he and his colleagues expected this dose-response relationship to some degree, “it was even more impressive than we intuitively expected,” he said.

Given that nearly half (47.8 percent) of patients did not receive all three processes in 2014, stepping up use of these strategies might further improve SAB outcomes, the researchers said.

“The management of Staphylococcus aureus bacteremia, for all its frequency and severity, remains remarkably unencumbered by data,” Dr. Vance Fowler, an infectious disease specialist at Duke University Medical Center, in Durham, North Carolina, told Reuters Health by email. The new study “makes an important step” toward addressing this deficit, he said.

“What I found particularly reassuring was that while each of the three strategies was independently associated with improved outcome, there was also an additive effect so that the more of the three treatment strategies were employed, the better the patient outcome,” said Dr. Fowler, who conducts research on determinants of outcome in patients with SAB but was not involved in the current study.

He noted that the study’s results “are profoundly gratifying personally,” because his own research in the past two decades has demonstrated the importance of echocardiography, consultation with an infectious disease specialist, and antistaphylococcal beta-lactam antibiotics when susceptibilities allow as interventions for SAB. The study’s findings “inform the medical community that these strategies should be regarded as standard of care wherever they are available,” Dr. Fowler said.